A horrific "game," where participants (typically adolescents with permanent erections and nothing better to do) sit together (often in formation around a focus, say a tv or computer screen) watching porn, and masturbating furiously. The criteria for "winning"/losing vary from game to game, but there can be unpleasant consequences for he who shoots before/after everyone else. Most often, however, whoever fails to
shoot before the allotted
time has elapsed is said to have lost.
See:
bukkake
M: Heard things got pretty wild the other
night, what happened?
H: They were playing beat the
clock..
M: Seriously? That's really
nasty.
H: Haha yeah, isn't it?
M: *sigh* .. The inhumanity..